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Commit a0652fc9 authored by Paul Mackerras's avatar Paul Mackerras
Browse files

powerpc: Unify the 32 and 64 bit idle loops 



This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle
loops.  It brings over the concept of having a ppc_md.power_save
function from 32-bit to ARCH=powerpc, which lets us get rid of
native_idle().  With this we will also be able to simplify the idle
handling for pSeries and cell.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 55aab8cd

arch/powerpc/kernel/Makefile

+3 −3
Original line number Diff line number Diff line
@@ -12,12 +12,12 @@ endif 


obj-y				:= semaphore.o cputable.o ptrace.o syscalls.o \

				   irq.o align.o signal_32.o pmc.o vdso.o \

				   init_task.o process.o systbl.o

				   init_task.o process.o systbl.o idle.o

obj-y				+= vdso32/

obj-$(CONFIG_PPC64)		+= setup_64.o binfmt_elf32.o sys_ppc32.o \

				   signal_64.o ptrace32.o \

				   paca.o cpu_setup_power4.o \

				   firmware.o sysfs.o idle_64.o

				   firmware.o sysfs.o

obj-$(CONFIG_PPC64)		+= vdso64/

obj-$(CONFIG_ALTIVEC)		+= vecemu.o vector.o

obj-$(CONFIG_POWER4)		+= idle_power4.o
@@ -34,6 +34,7 @@ obj-$(CONFIG_IBMEBUS) += ibmebus.o 
obj-$(CONFIG_GENERIC_TBSYNC)	+= smp-tbsync.o

obj64-$(CONFIG_PPC_MULTIPLATFORM) += nvram_64.o

obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o

obj-$(CONFIG_6xx)		+= idle_6xx.o



ifeq ($(CONFIG_PPC_MERGE),y)
@@ -51,7 +52,6 @@ obj-$(CONFIG_PPC64) += misc_64.o dma_64.o iommu.o 
obj-$(CONFIG_PPC_MULTIPLATFORM)	+= prom_init.o

obj-$(CONFIG_MODULES)		+= ppc_ksyms.o

obj-$(CONFIG_BOOTX_TEXT)	+= btext.o

obj-$(CONFIG_6xx)		+= idle_6xx.o

obj-$(CONFIG_SMP)		+= smp.o

obj-$(CONFIG_KPROBES)		+= kprobes.o

obj-$(CONFIG_PPC_UDBG_16550)	+= legacy_serial.o udbg_16550.o

arch/powerpc/kernel/entry_32.S

+6 −2
Original line number Diff line number Diff line
@@ -135,10 +135,10 @@ transfer_to_handler: 
	mfspr	r11,SPRN_HID0

	mtcr	r11

BEGIN_FTR_SECTION

	bt-	8,power_save_6xx_restore	/* Check DOZE */

	bt-	8,4f			/* Check DOZE */

END_FTR_SECTION_IFSET(CPU_FTR_CAN_DOZE)

BEGIN_FTR_SECTION

	bt-	9,power_save_6xx_restore	/* Check NAP */

	bt-	9,4f			/* Check NAP */

END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)

#endif /* CONFIG_6xx */

	.globl transfer_to_handler_cont
@@ -157,6 +157,10 @@ transfer_to_handler_cont: 
	SYNC

	RFI				/* jump to handler, enable MMU */



#ifdef CONFIG_6xx	

4:	b	power_save_6xx_restore

#endif



/*

 * On kernel stack overflow, load up an initial stack pointer

 * and call StackOverflow(regs), which should not return.

arch/powerpc/kernel/idle_64.c→arch/powerpc/kernel/idle.c

+40 −39
Original line number Diff line number Diff line
@@ -2,13 +2,17 @@ 
 * Idle daemon for PowerPC.  Idle daemon will handle any action

 * that needs to be taken when the system becomes idle.

 *

 * Originally Written by Cort Dougan (cort@cs.nmt.edu)

 * Originally written by Cort Dougan (cort@cs.nmt.edu).

 * Subsequent 32-bit hacking by Tom Rini, Armin Kuster,

 * Paul Mackerras and others.

 *

 * iSeries supported added by Mike Corrigan <mikejc@us.ibm.com>

 *

 * Additional shared processor, SMT, and firmware support

 *    Copyright (c) 2003 Dave Engebretsen <engebret@us.ibm.com>

 *

 * 32-bit and 64-bit versions merged by Paul Mackerras <paulus@samba.org>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version
@@ -29,18 +33,43 @@ 
#include <asm/machdep.h>

#include <asm/smp.h>



extern void power4_idle(void);

#ifdef CONFIG_HOTPLUG_CPU

#define cpu_should_die()	(cpu_is_offline(smp_processor_id()) && \

				 system_state == SYSTEM_RUNNING)

#else

#define cpu_should_die()	0

#endif



void default_idle(void)

/*

 * The body of the idle task.

 */

void cpu_idle(void)

{

	unsigned int cpu = smp_processor_id();

	set_thread_flag(TIF_POLLING_NRFLAG);

	if (ppc_md.idle_loop)

		ppc_md.idle_loop();	/* doesn't return */



	set_thread_flag(TIF_POLLING_NRFLAG);

	while (1) {

		if (!need_resched()) {

			while (!need_resched() && !cpu_is_offline(cpu)) {

		ppc64_runlatch_off();



		while (!need_resched() && !cpu_should_die()) {

			if (ppc_md.power_save) {

				clear_thread_flag(TIF_POLLING_NRFLAG);

				/*

				 * smp_mb is so clearing of TIF_POLLING_NRFLAG

				 * is ordered w.r.t. need_resched() test.

				 */

				smp_mb();

				local_irq_disable();



				/* check again after disabling irqs */

				if (!need_resched() && !cpu_should_die())

					ppc_md.power_save();



				local_irq_enable();

				set_thread_flag(TIF_POLLING_NRFLAG);



			} else {

				/*

				 * Go into low thread priority and possibly

				 * low power mode.
@@ -48,44 +77,16 @@ void default_idle(void) 
				HMT_low();

				HMT_very_low();

			}



			HMT_medium();

		}



		HMT_medium();

		ppc64_runlatch_on();

		preempt_enable_no_resched();

		schedule();

		preempt_disable();

		if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)

		if (cpu_should_die())

			cpu_die();

	}

}



void native_idle(void)

{

	while (1) {

		ppc64_runlatch_off();



		if (!need_resched())

			power4_idle();



		if (need_resched()) {

			ppc64_runlatch_on();

		preempt_enable_no_resched();

		schedule();

		preempt_disable();

	}



		if (cpu_is_offline(smp_processor_id()) &&

		    system_state == SYSTEM_RUNNING)

			cpu_die();

	}

}



void cpu_idle(void)

{

	BUG_ON(NULL == ppc_md.idle_loop);

	ppc_md.idle_loop();

}



int powersave_nap;

arch/powerpc/kernel/idle_6xx.S

+0 −15
Original line number Diff line number Diff line
@@ -87,19 +87,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP) 
	cmpwi	0,r3,0

	beqlr



	/* Clear MSR:EE */

	mfmsr	r7

	rlwinm	r0,r7,0,17,15

	mtmsr	r0



	/* Check current_thread_info()->flags */

	rlwinm	r4,r1,0,0,18

	lwz	r4,TI_FLAGS(r4)

	andi.	r0,r4,_TIF_NEED_RESCHED

	beq	1f

	mtmsr	r7	/* out of line this ? */

	blr

1:	

	/* Some pre-nap cleanups needed on some CPUs */

	andis.	r0,r3,HID0_NAP@h

	beq	2f
@@ -220,8 +207,6 @@ _GLOBAL(nap_save_msscr0) 
_GLOBAL(nap_save_hid1)

	.space	4*NR_CPUS



_GLOBAL(powersave_nap)

	.long	0

_GLOBAL(powersave_lowspeed)

	.long	0

arch/powerpc/kernel/idle_power4.S

+0 −15
Original line number Diff line number Diff line
@@ -49,21 +49,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP) 
	cmpwi	0,r4,0

	beqlr



	/* Clear MSR:EE */

	mfmsr	r7

	li	r4,0

	ori	r4,r4,MSR_EE

	andc	r0,r7,r4

	mtmsrd	r0



	/* Check current_thread_info()->flags */

	clrrdi	r4,r1,THREAD_SHIFT

	ld	r4,TI_FLAGS(r4)

	andi.	r0,r4,_TIF_NEED_RESCHED

	beq	1f

	mtmsrd	r7	/* out of line this ? */

	blr

1:

	/* Go to NAP now */

BEGIN_FTR_SECTION

	DSSALL